A know better than B
A比B在某方面更清楚
should know better than to do有否定意思,"应当知道做……不对"
例句：
I know Paris better than Rome.我对巴黎比对罗马熟悉.
And you know the procedure better than I do.你比我更清楚程序.
She should know better than to poke the animal with her umbrella.她应当知道不该用伞去捅动物.
She should know better than to spend all her money on chocolate.他应当明白把所有的钱花在实巧克力上是不对的.